lives in tannin stained stream water
- Size
- Length: 8–12 cm, Weight: 10–20 g
- Lifespan
- 3–5 years
- Diet
- Aquatic insects small crustaceans and insect larvae. Picks prey off bottom with downturned mouth in slow deep pools of coastal streams and wetlands.
- Habitat
- Small coastal streams and wetlands often in areas with sandy or muddy bottoms and plenty of overhanging vegetation. Fish of the coastal plain in tannin-stained water.
- Range
- Lowland streams throughout North Island and top of South Island. Most common in small coastal streams and wetlands with sandy or muddy bottoms nationwide.
- Endemism
- Endemic
- Main Threats
- Habitat loss from coastal development and stream modification. Water pollution from agricultural and urban runoff. Predation by introduced fish. Climate change affecting water temperature.
- Population
- Not Threatened. Common in lowland streams throughout North Island and top of South Island. Preference for coastal low-elevation habitats puts them in competition with introduced fish.
- Conservation Status
- Not Threatened
- Human Risk
- harmless
- Handling Note
- native freshwater galaxias, observe from bank to avoid disturbance
- Conservation Note
- Endemic freshwater fish; widespread in streams and rivers throughout New Zealand.
- Assessment
- NZTCS Freshwater Fishes (2023)
- Te Ao Māori
- The Flathead Galaxias does not have a widely recorded Māori name. This is likely because it was grouped with other small stream-dwelling fish. Today it is the fish of the coastal stream. It lives in the brown water. It hides under the overhanging banks. It stays away from the eels and the trout and the drainage pumps. Its obscurity reflects its modest size and hidden habits. Mana whenua observe these lowland indicators closely. The health of the coastal stream is tied to the presence of such species.
Flattened resident of the coastal stream. It hides under rocks and waits. The flathead galaxias has a long slender body. But the head is noticeably flattened from top to bottom. This is an adaptation for hiding under rocks and in tight spaces. The colour is mottled olive-brown to golden. Darker blotches often mark the sides. The mouth is large and slightly downturned. It is perfect for picking food off the bottom. A fish that looks like it was stepped on.
Bottom-huggers of the lowland stream. Flathead galaxias spend most of their time on or near the substrate. They hide under rocks and in root wads. They emerge at night to feed. They eat insects worms and small crustaceans. They pick them off the bottom with a downturned mouth. They are not strong swimmers. They prefer the slow deep pools where they can hover without expending too much energy. A fish that does not need to be fast.
It is the fish of the coastal plain. This landscape has been heavily modified by farming drainage and development. Flathead galaxias are still common in the remaining healthy streams. But those streams are getting harder to find. Coastal development water pollution and introduced fish have taken their toll. A fish that is losing its home.
To find a flathead galaxias is to find a piece of old New Zealand. It is a small flat-headed fish in a tannin-stained stream. It serves as a reminder of what the lowlands looked like before the drains went in. Before the water was turned to pasture.
The stream is brown. The water is slow. The flathead hides under a rock. Its flattened body is pressed against the gravel. It does not know that the stream is dying. It does not know that the pasture is taking over.
It just hides. That is all it can do.